Does the tapping noise stay in the engine even when it warms up? I had a ZR750 with a tapping problem, it was noisy when cold but fine when warm. I replaced the camchain & tensioner, did the shims, compression test etc, etc.
It was hard to tell where the noise was coming from but it sounded like it was from the top-end, it turned out that one of the big end bearings was shot.
Do as M says & check the valve clearances first, if they're okay then you could getting into the expensive stuff.
steo
May 2010
early kwaks are known for pittted camshafts.was that checked? also valve clearance?
m
May 2010
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